Dzogchen / As it is [1]

~Tulku Urgyen Rinpoche

The main image of Dharmadhatu is that of space - the 'space of all things' within which all phenomena manifest, abide and dissolve back into. This is similar to physical space, which is like a container within which the remaining four elements appear, abide and disappear. These four elements do not come out of any other source; they emerge from space itselt. They do not remain anywhere else other than within space; neither do they go anywhere outside of space. 

In the same way, dharmadhatu is the basic environment of all phenomena, whether they belong to samsara or nirvana. It encompasses whatever appears and exists, including the worlds and all beings. Everything takes place within and dissolves back into the state of dharmadhatu. Dharmadhatu encompasses all of samsara and nirvana -it doesn't include only nirvana and exclude samsara; it's not like that, External phenomena appear within space, remain within space and disappear within space again. 

Is there any place where earth, water, fire and wind can go that is outside space? Don't they always remain within space? When they disintegrate, isn't it within space that they dissolve? Is there any place at all to go to which is beyond or outside space, which is somewhere other than space? 

Please understand very well this symbolic resemblance between dharmadhatu and physical space. The relationship between dharmadhatu, dharmakaya and dharmadhatu wisdom is like the relationship between a place, a person and the person's mind. If there is no place, there is no environment for the person to exist in; and there is no person unless that person also has a mind dwelling in the body. In the same' way, the main field or realm called dharmadhatu has the nature of dharmakaya. Dharmakaya has the quality of dharmadhatu wisdom, which is like the mind aspect.

As it is / Rangjung Yeshe Publications